Hi Mr. Yeh,
I have a gigabyte GA-M57SLI-S4 rev. 2.0 motherboard, a new AMD Phenom II 940 cpu, 4 sticks of Kingston 1x1 Ram PC5300, two nVidia 9800gt (512k) cards in SLI. I am running Windows Vista SP1 32 bit with all the current updates. Power supply is 650w. Bios is version FHD which should be correct. When I go into the bios to overclock the cpu using the multiplier to go from 15 to 16 the computer will boot just fine. The problem is that super pi actual runs much slower. Stock it takes about 23.5 seconds, changing the bios and it takes over 60 seconds to perform super pi to 1 million decimal places. All my drivers are up to date.

I also have the same problem trying to change any other bios settings to overclock the cpu such as FSB.

I have nVidia's overclocking software in windows for the video cards, which also has settings for the FSB. Using this software I can successful overclock to 3.35 gig from the stock 3.0 by changing the FSB from 200 to 224. At this point I can run super pi in about 21.2 seconds which lets me know it's working just fine. I have also use gigabytes overclocking software in windows with a little less success, but far better than going into the bios.

My games also reflect the above results with slower frames per second adjusting bios settings and higher frames per second using the nVidia software. What could possibly cause this disparity? All changes are made only to the FSB.